Device for detonating explosive charges in a liquid medium

ABSTRACT

In a device for detonating an explosive charge in a liquid medium by closing an electric circuit comprising a first conductive member passing through an explosive charge contained in a nose end portion of a cartridge body, the other end of the body having a flared portion and serving as a means for seating the body in an immersed end of a charging tube, and a second conductive member for electrically connecting the first conductive member to terminals of a current source, an improvement of the cartridge body being that the cartridge body is formed of two portions each being equipped with a conductive circuit member. One of these portions is a female element having an insulating inner wall and a conductive outer wall in which these two walls define a chamber containing the explosive charge and the inner wall having a contact of the electric circuit. The other portion is in the form of a hollow male element having a closed end portion adapted to be received in a closed end portion of the female element. The male element includes an insulating outer wall and a conductive inner wall provided with a contact member adapted to contact the contact of the female element when the male element is received therein.

D United States Patent [151 3,685,448 Magneville [4 1 Aug. 22,1972

[54] DEVICE FOR DETONATING EXPLOSIVE CHARGES IN A LIQUID Primary Examiner-Verlin R. Pendegrass MEDIUM Attorney-Craig, Antonelli, Stewart & Hill [72] Inventor: 2:11; Magnevllle, Vemourllet, [57] aBSTR aCT In a device for detonating an explosive charge in a [73] Asslgnee' :nsutut 2 fa liquid medium by closing an electric circuit compris- Y ing a first conductive member passing through an ex- S e eme fame plosive charge contained in a nose end portion of a [22] Filed; April 3, 1970 tclartrildge body, 3e other end of the tbody havingha are portion an serving as a means or seating t e [21] Appl" 25314 body in an immersed end of a charging tube, and a second conductive member for electrically connecting [30] Foreign Application Priority Data the first conductive member to terminals of a current 1969 F 6910364 source, an improvement of the cartridge body being Apnl that the cartridge body is formed of two portions each being equipped with a conductive circuit member. [52] US. one of these portions is a female element having an [51] '3" 46 70 insulating inner wall and a conductive outer wall in [58] held 0 Sean which these two walls define a chamber containing the explosive charge and the inner wall having a contact of the electric circuit. The other portion is in the form [56] References C'ted of a hollow male element having a closed end portion UNITED STATES PATENTS adapted to be received in a closed end portion of the female element. The male element includes an insulatprovided a contact member adapted to contact the contact 3 Claims, 1 Drawing Figure ing outer wall and a conductive inner wall with of the female element when the male element is received therein.

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DCAZWC 7 9 a 9 a a P'ATENTED AUG 22 I972 DEVICE FOR DETONATING EXPLOSIVE CHARGES IN A LIQUID MEDIUM In US. Pat. No. 3,524,519 to Cholet et al., issued Aug. 18, 1970 and assigned to the assignee of this application, there is described a device for detonating explosive cartridges in a liquid medium by closing an electric circuit, in which the cartridge body is provided internally with electric conductors passing across .the explosive charges and destructible by flowing a high electrical energy therethrough and is provided with means for feeding said conductors with electrical ener- There are also disclosed in the patent cartridges specially adapted to said device, comprising an explosive charge contained in a cylindrical enclosure, and provided with a conducting coating layer on one part of the external surface of said enclosure and a conducting coating layer on one part of the internal surface of said enclosure.

The present specification has for object to disclose a cartridge of this type having the advantage of being easily manufactured and consequently of being manufactured at a low price.

This new cartridge is composed of the following elements: an insulating cylindrical enclosure having a bottom end and serving as a carrier for the whole assembly, a tube of conducting material having a. bottom end and slidably mounted into the cylindrical enclosure with its bottom end registering with the bottom end of said cylindrical enclosure, said two bottom ends being electrically connected through a first contact member, a plug of insulating material having at least one tubular part and a circular plane wall with a second contact member passing therethrough, said plug fitting on one end of the cylindrical enclosure in such a way that the contact members join each other a cap of conducting material containing an explosive charge and fitting on said insulating plug, an explosive conductor passing across the explosive charge and connecting the second contact member to the conducting wall of the cap.

This new cartridge according to the invention will be further described more in detail with reference to the accompanying drawing wherein elements identical to those already described in the parent specification have the same reference numerals.

As shown in the drawing, the cartridge comprises a female element and a male element fitting therein. The male element comprises a cylindrical enclosure 7 of insulating material, extended at one end thereof with a widened head 8 and closed at the other end by a bottom 23. It further comprises a second part formed of a metallic tube 24, e.g., of aluminum, having an external diameter substantially equal to the internal diameter of the cylindrical enclosure 7 and which fits therein. The tube 24, the length of which is greater than that of the enclosure 7 including the extension by the head 8, is Open at its end which is the closest to the head 8 and is provided at its other end with a bottom 25 which bears against the bottom 9 of the insulating enclosure. A metal plug 26, acting as a contactor, electrically connects the two bottoms 23 and 25.

The female element of the cartridge. is formed in part of a plug of insulating material, e.g., plastic material, comprising two tubular portions 27 and 28 on both sides of a circular plane wall 29. The tubular portion 27 has an internal diameter substantially equal to the extemal diameter of the enclosure 7 so as to fit thereon. Two grooves 30 and 30 can be provided respectively at that end of the enclosure 7 which is the closest to the bottom 23 and at the open end of the tubular portion 27, so as to keep the enclosure 7 fitted in the tubular portion 27. The tubular section 28, defining a tubular recess, has an external diameter lower than that of the portion 27. A metal plug 31 is provided across the wall 29 in its common part with the tubular section 28 in order to be used as electric contact member. When the end of the enclosure 7 fits in the tubular portion 27, the plug 31 comes into contact with the plug 26. I

The female element of the cartridge further comprises a metal cap 32, e.g., of aluminum, destructible by explosion. This cap, of cylindrical shape, is closed at one end withv a bottom 33 and open at the other end. Its internal diameter, at this open end, is substantially equal to the externalv diameter of the tubular portion 27 so as to fit thereon. The cap 32 contains an explosive charge 10, up to the level of a shoulder 34 of the tubular portion of the cap, which shoulder is provided for housing the circular plane wall 29 of larger diameter. When the cap is fitted on the insulating plug (27, 28, 29), the explosive charge 10 fills the cap up to the wall 29, leaving free the volume corresponding to the tubular section 28 whose length is smaller than that of the cap.

An exploding wire 35 connected at one end to the contact plug 31 and at the other end to the cap 32, passes partly through the tubular section 28 of the insulating plug, and partly through the explosive charge 10.

The so-assembled cartridge is adapted to the device described in the parent specification and the firing thereof is carried out in the manner described in the patent.

The portion of the electric circuit regarding the cartridge comprises: the aluminum tube 24, the contact plug 26, the contact plug 31, the exploding wire 35 and the metal wall of the cap 32. The insulating tubular section 28 is provided for preventing any short-circuit between the plug 31 and the closest portion of the wall of the cap 32.

At the time selected for the explosion the circuit is fed with electric current and the wire 35 explodes and the explosive charge therewith, thereby destroying the cartridge.

The cartridge according to the invention is formed of simple elements whose manufacture is easy and the cost is low. It also exhibits a high tightness, of great interest in the case of a circuit which must be operated within conducting water.

What we claim is:

1. In a device for detonating an explosive charge in a liquid medium by closing an electric circuit comprising first conductor means passing through an explosive charge contained in a nose end portion of a cartridge body, the other end thereof terminating in a head having a transverse cross section greater than that of the remainder of said body and serving as a means for seating said body in an immersed end of a charging tube, and a secondv conducting means for electrically connecting the first conductor means to terminals of a current source, an improvement of the cartridge body compnsmg:

a female element including an external conducting wall and an internal insulating wall provided with a contact member, the external and internal walls delimitating a recess for containing the explosive charge; and

a hollow male fitting element including a closed end portion adapted to fit in a closed end portion of said female element and terminating at the other end thereof with said head, the male element including an insulating external wall, an internal conducting wall with a bottom end provided with a contact member for electrical connection with the contact member of the female element.

2. In a device for detonating an explosive charge in a liquid medium by closing an electric circuit comprising a first conductor means passing through the explosive charge contained in a nose end portion of a cartridge body, the other end thereof terminating in a head having a transverse cross section greater than that of the remainder of said body and serving as a means for seating said body in an immersed end.of a charging tube and second conducting means for electrically connecting the first conductor means to the terminals of a current source, an improvement of the cartridge comprising:

a male fitting element including a cylindrical enclosure (7) of insulating material, extended at one end with a widened head (8) and closed at the other end by the bottom (23) of the enclosure, a tube (24) of conducting material whose external diameter is substantially the internal diameter of the enclosure (7) and having a length greater than that of the enclosure (7 including the head extension (8), said tube being provided at one end thereof with a bottom (25) adapted to bear against the bottom (23) of the enclosure when said tube is slidably introduced into said enclosure, said tube bottom end (25 being electrically connected through the enclosure bottom (23) to a contact member (26), at least partly externally to said enclosure bottom; and a female fitting element including a plug of insulating material having at least one tubular portion (27) of an internal diameter substantially equal to the external diameter of the insulating enclosure for fitting the latter therein, the bottom (29) of said tubular portion being provided with a contact member (31) passing therethrough and bearing, on one side of said bottom, against the contact member (26), when the enclosure is fitted in said tubular portion, and a cap (32) of conducting material, destructible by explosion, having a cylindrical shape closed at one end with a bottom (33) and the other end of which has an internal diameter substantially equal to the external diameter of the tubular portion (27) of the insulating plug so that the latter can be fitted therein, said cap containing the explosive charge 3. A device according to claim 2 wherein the insulating plug comprises a tubular recess (28) on the side opposite to the tubular portion (27) of the plug with respect to the bottom thereof, said tubular recess (28) providing a passage to that part of the conductor (35),

passing through the bottom of said tubular recess,

which is the closest to the contact member (31 

1. In a device for detonating an explosive charge in a liquid medium by closing an electric circuit comprising first conductor Means passing through an explosive charge contained in a nose end portion of a cartridge body, the other end thereof terminating in a head having a transverse cross section greater than that of the remainder of said body and serving as a means for seating said body in an immersed end of a charging tube, and a second conducting means for electrically connecting the first conductor means to terminals of a current source, an improvement of the cartridge body comprising: a female element including an external conducting wall and an internal insulating wall provided with a contact member, the external and internal walls delimitating a recess for containing the explosive charge; and a hollow male fitting element including a closed end portion adapted to fit in a closed end portion of said female element and terminating at the other end thereof with said head, the male element including an insulating external wall, an internal conducting wall with a bottom end provided with a contact member for electrical connection with the contact member of the female element.
 2. In a device for detonating an explosive charge in a liquid medium by closing an electric circuit comprising a first conductor means passing through the explosive charge contained in a nose end portion of a cartridge body, the other end thereof terminating in a head having a transverse cross section greater than that of the remainder of said body and serving as a means for seating said body in an immersed end of a charging tube and second conducting means for electrically connecting the first conductor means to the terminals of a current source, an improvement of the cartridge comprising: a male fitting element including a cylindrical enclosure (7) of insulating material, extended at one end with a widened head (8) and closed at the other end by the bottom (23) of the enclosure, a tube (24) of conducting material whose external diameter is substantially the internal diameter of the enclosure (7) and having a length greater than that of the enclosure (7) including the head extension (8), said tube being provided at one end thereof with a bottom (25) adapted to bear against the bottom (23) of the enclosure when said tube is slidably introduced into said enclosure, said tube bottom end (25) being electrically connected through the enclosure bottom (23) to a contact member (26), at least partly externally to said enclosure bottom; and a female fitting element including a plug of insulating material having at least one tubular portion (27) of an internal diameter substantially equal to the external diameter of the insulating enclosure for fitting the latter therein, the bottom (29) of said tubular portion being provided with a contact member (31) passing therethrough and bearing, on one side of said bottom, against the contact member (26), when the enclosure is fitted in said tubular portion, and a cap (32) of conducting material, destructible by explosion, having a cylindrical shape closed at one end with a bottom (33) and the other end of which has an internal diameter substantially equal to the external diameter of the tubular portion (27) of the insulating plug so that the latter can be fitted therein, said cap containing the explosive charge (10).
 3. A device according to claim 2, wherein the insulating plug comprises a tubular recess (28) on the side opposite to the tubular portion (27) of the plug with respect to the bottom thereof, said tubular recess (28) providing a passage to that part of the conductor (35), passing through the bottom of said tubular recess, which is the closest to the contact member (31). 